Overexpression of p53 in human breast cancer

An overexpression of the p53 oncogene was found in 25% to approx. 50% of primary breast carcinomas. The aim of our study was to determine the correlation between p53 expression and established prognostic factors in breast cancer. Immunohistochemical evaluation of 211 breast cancers with the monoclonal antibody (MoAb) to p53 suppressor gene (BP53-12) was performed. A positive p53 overexpression was detected in 79 (37,4%) tumors. Tumors with positive p53 overexpression showed a significant relationship to high PCNA (p<0.00006) and high Ki67 value (p<0.002). No correlations were found between p53-positve tumors and tumor size, grading, lymph node status. Tumors with p53-positive overexpression had a low or negative receptor status. P53 was significantly correlated with high growth fractions. A significantly shorter recurrence free survival was correlated with high p53 values. These results suggest that p53 oncoprotein may be a marker of more aggressive carcinomas.